Add syntax highlighting and LSP for Dockerfiles(#6905)

[d1y]

Release Notes:

• Added Dockerfile syntax highlighting and LSP support

[d1y]

In #6905, I can't wait, I need this so much

[d1y]

I think when the plugin system is truly perfected, it can be downgraded to the plugin level, but before that, I need it 🤒

[SomeoneToIgnore]

I see that people actually submit extensions already, here's one for Java, for example: zed-industries/extensions#57

Would it make sense to transfer it there?

[d1y]

I see that people actually submit extensions already, here's one for Java, for example: zed-industries/extensions#57

Would it make sense to transfer it there?

The current plug-in system is not perfect enough, lsp-server does not support it yet (I am not sure, at least I have not seen anything that does this, and embeds a binary (re-exec)

[SomeoneToIgnore]

Ok, re-checked on extensions (and noticed no LSP support yet) and this PR (seems good, and LSP actually doing navigation & formatting, so sort of useful).

Let's get that in, thank you for the pushing it over the last mile.